Minor atcommand.c cleanup

Removed many wrong/pointless nullpo_ calls, Special Thanks to Haruna, ossi0110

Signed-off-by: shennetsind <ind@henn.et>
Item Drop (from any source) Processing Improvement

Signed-off-by: shennetsind <ind@henn.et>
Merge branch 'master' of https://github.com/HerculesWS/Hercules
Minor HPM Update

Attempting to hook to a unknown hooking point will now display a message.
Added support for item bonuses
Check https://github.com/HerculesWS/StaffPlugins/tree/master/shennetsind/bCoolDownRate for a demonstration.

Signed-off-by: shennetsind <ind@henn.et>